Engine Oil Change: Lycoming O-320 and O-360 (2024)

This oil change procedure is consistent with guidance from my A&P and Lycoming. I share it here since it may be helpful as a guide for others. However, review it yourself or with your A&P, and make whatever changes are needed for your particular engine in your particular airplane.

Tools/Equipment needed:

At the field:

• Oil Filter, Champion CH-48110
  • CH-48111 is also approved for this engine, but is longer and requires more clearance
  • BEWARE: the Tempest part for CH-48111 is physically longer than the Champion part!
• Oil, 7 qts. 20w50, or straight weight: 50wt in summer, 40wt in winter
  • max capacity 8 quarts
  • if you fill past 7 quarts, the extra oil just blows out the breather
• Camguard additive @ 5% = 11 oz.
• Funnel for (re)filling oil
• Bucket (at least 8 qt capacity) & hose for draining oil
• Small bowl for capturing oil from filter
• Oil analysis kit (Blackstone, optional)
• Oil quick-drain hose, ID = 3/8"
• Safety wire, wiring tool, wire cutters
• Torque wrench adjustable to 17 ft-lbs. / 204 in-lbs.
• Socket for oil filter

At home:

• oil filter cutter (opener)

Procedure

At the field:

1. Ensure engine is at operating temperature (immediately after flying)
2. Remove top engine cowl
   1. Bottom cowl is connected to air filter and is not necessary to remove
3. Unscrew oil dipstick, leave in place (provides air gap to facilitate draining)
4. Connect hose from quick drain to bucket
5. Open quick drain to drain the oil
6. Capture a mid-drain sample for UOA (about 3 oz.)
7. Remove the old filter, using small bowl to capture oil
   1. Cut the safety wire and discard
   2. Unscrew the filter
8. Set old filter aside (bring it home to cut open)
   1. Ensure it is sealed so crud can't get inside
9. Remove oil screen cover & inspect/clean oil screen
10. Install new oil filter:
    1. wipe gasket with oil to facilitate sealing
    2. thread on until the gasket touches engine block
    3. using torque wrench, tighten to 17 ft-lbs / 204 in-lbs (this is firm hand tight)
    4. secure with safety wire
11. Close quick drain
12. Refill engine with new oil
    1. add through dipstick tube using funnel
    2. after first 3 quarts, add 11 oz. Camguard
    3. 6.5 - 7 qts total – anything more blows out the breather
13. Inspect open engine bay, battery, etc. for leaks, loose wires, etc.
14. Remove all tools, wire, etc. from engine bay
15. Reinstall engine cowl and inspect fit - e.g. baffles
    1. IRAN cowling fittings, screws, washers
    2. Ensure wires to taxi & landing lights are connected
16. Clear work area for engine run / propeller
17. Start the engine and do a 2000 RPM runup
    1. check oil pressure after starting
    2. let engine idle for a few moments
    3. run up to 2000 RPM for a moment while checking oil pressure
18. Clean up area – tools, oil filter, sample kit, etc.
19. After cleanup, at least 15 mins after engine shutdown, check the engine oil level on the dipstick
    1. after cleanup gives time for the oil to settle into the pan
    2. should be above 6 qts

At home:

1. Use filter cutter to open filter
2. Cut out paper element and inspect pleats for metal particles or other contaminants
3. Add an engine log entry for this procedure
4. Optional: Mail sample for UOA

A few comments:

I prefer Tempest oil filters, which I feel are better as well as cheaper than the Champions.

Most Continental engines have dedicated oil fill points, which may not require a funnel. Continental dipstick ports are much too small to use for filling. I found the absence of this one of the most annoying parts of our switch from a Continental to a Lycoming design.

My favorite oil-fill "funnel" is a bottle of the same kind of oil with the bottom cut off. With the spout of of the funnel bottle inserted into the filler port, this will usually hold the full bottle quite firmly while it's draining into the engine, even in gusty winds.

Safety-wiring is as much art as mechanics. There are specs (usually 6 to 8 twists per inch, and usually .032 thickness in stainless wire for filters) for how it's done, and a safety-wire plier will help. But the most important thing to remember is that it must "pull" the filter or fastener in the direction that would tighten it -- in other words, it must be run so it prevents whatever it's attached to from loosening. This can require some planning when both ends of the wire are attached to parts that can turn.

The drain hose should fit snugly. I have had 5 different aircraft types, an no two used the same ID for the quick-drain hose. I have had some that were snug enough that I could pull them to open the quick-drain. If yours isn't snug or long enough, a length of heater hose from an auto supply will solve the problem quite cheaply.

I would recommend using a paint strainer. While draining..

Folks spend $ on oil samples but ignore basics.

magman said:

It’s best to close the Quick Drain before adding oil!

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I agree, hence step 11.

Aeromot said:

...I prefer Tempest oil filters, which I feel are better as well as cheaper than the Champions....

Click to expand...

Agreed. However, the Tempest filter part CH-48111 is physically longer than the Champion. This burned me a few years ago because the Champion used to fit in my airplane, but when I bought the Tempest it did not fit - it was too long. When I buy Tempest oil filters I can only use CH-48110.

With CH-48110 they are both the same size.

This is very old, but it's the next step:
https://www.demonick.com/flying/Oil.Filter.Inspection/index.html

This time of year it is wise to consider pressure testing exhaust system in place

at this time. It will soon be cold in some regions and this could save your life.

btw. You don’t want to do the oil change soon before the Annual

as the IA will want to pull screen/ filter.

” Can’t see it , can’t sign it” is common.

Domenick said:

This is very old, but it's the next step:
https://www.demonick.com/flying/Oil.Filter.Inspection/index.html

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That's a useful detail of "At Home" steps 1 and 2. I'll emphasize to be careful when cutting open the filter and cutting out the paper element, in order to avoid creating metal particles that will make you think they came from the engine.

Also, using vodka to clean things sounds like alcohol abuse

Here is the filter cutter I use, no paint or metal chips are produced when using it. If you have a vice it is a one handed operation.

Domenick said:

Where do you get one?

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I got mine from Aircraft Spruce. Made by Tom and appears to be the cheapest one they sell. I have used it since 2018 and 1300 hrs of oil changes. Holding up well.

Thanks. For those interested: (Only $66 and shipping)